1. Field of the Invention
The present invention relates, for example, to a bias circuit and an amplifier using the same.
2. Description of the Related Art
Conventionally, a technique disclosed as one of techniques to generate a bias current for use in an amplifier circuit uses a bias circuit having a positive temperature characteristic, a bias circuit having a negative temperature characteristic, and a switch which detects the temperature of the amplifier circuit and switches between the two bias circuits according to the detected temperature.
In the case of this technique, the temperature of the amplifier circuit is detected, and the two bias circuits are switched over by the switch according to the detected temperature, whereby the distortion at low temperatures can be suppressed and the decrease in gain of the amplifier circuit at high temperatures can be suppressed (see, for example, JP-A 2007-336224 (KOKAI)).